CompTIA A+ Certification Practice Questions and
Answers & Detailed Rationales UPDATED 2026
1. What is the primary function of the BIOS in a computer system?
A. Manage file storage
B. Load the operating system
C. Provide internet connectivity
D. Run applications
Answer: B
Rationale:
BIOS (Basic Input/Output System) initializes hardware during boot and loads
the operating system into memory via the bootloader.
2. Which component is considered volatile memory?
A. SSD
B. ROM
C. RAM
D. HDD
Answer: C
Rationale:
RAM loses all stored data when power is turned off, making it volatile memory.
3. What is the purpose of an IP address?
A. Identify a device on a network
,B. Encrypt data transmission
C. Store MAC addresses
D. Provide antivirus protection
Answer: A
Rationale:
An IP address uniquely identifies devices on a network for communication.
4. Which command is used to test network connectivity?
A. ipconfig
B. ping
C. netstat
D. tracert
Answer: B
Rationale:
The ping command checks connectivity between devices using ICMP packets.
5. What does DHCP do?
A. Encrypt data
B. Assign IP addresses automatically
C. Block malware
D. Route packets
Answer: B
Rationale:
DHCP automatically assigns IP addresses and network configuration settings.
,6. Which device operates at Layer 2 of the OSI model?
A. Router
B. Switch
C. Firewall
D. Modem
Answer: B
Rationale:
Switches operate at the Data Link Layer (Layer 2) using MAC addresses.
7. What is the function of a firewall?
A. Increase CPU speed
B. Filter network traffic
C. Store backups
D. Assign IP addresses
Answer: B
Rationale:
Firewalls control incoming and outgoing network traffic based on security rules.
8. Which storage type offers the fastest performance?
A. HDD
B. SSD
C. Optical drive
D. Tape drive
Answer: B
, Rationale:
SSD (Solid State Drive) uses flash memory, making it much faster than
mechanical drives.
9. What does POST stand for?
A. Power On Self Test
B. Program Output System Test
C. Primary Operating System Tool
D. Pre-Operational System Transfer
Answer: A
Rationale:
POST checks hardware functionality when a computer starts.
10. Which connector is commonly used for modern monitors?
A. VGA
B. HDMI
C. PS/2
D. Serial
Answer: B
Rationale:
HDMI supports high-definition audio and video signals.
11. What is the purpose of DNS?
A. Encrypt data
B. Convert domain names to IP addresses
Answers & Detailed Rationales UPDATED 2026
1. What is the primary function of the BIOS in a computer system?
A. Manage file storage
B. Load the operating system
C. Provide internet connectivity
D. Run applications
Answer: B
Rationale:
BIOS (Basic Input/Output System) initializes hardware during boot and loads
the operating system into memory via the bootloader.
2. Which component is considered volatile memory?
A. SSD
B. ROM
C. RAM
D. HDD
Answer: C
Rationale:
RAM loses all stored data when power is turned off, making it volatile memory.
3. What is the purpose of an IP address?
A. Identify a device on a network
,B. Encrypt data transmission
C. Store MAC addresses
D. Provide antivirus protection
Answer: A
Rationale:
An IP address uniquely identifies devices on a network for communication.
4. Which command is used to test network connectivity?
A. ipconfig
B. ping
C. netstat
D. tracert
Answer: B
Rationale:
The ping command checks connectivity between devices using ICMP packets.
5. What does DHCP do?
A. Encrypt data
B. Assign IP addresses automatically
C. Block malware
D. Route packets
Answer: B
Rationale:
DHCP automatically assigns IP addresses and network configuration settings.
,6. Which device operates at Layer 2 of the OSI model?
A. Router
B. Switch
C. Firewall
D. Modem
Answer: B
Rationale:
Switches operate at the Data Link Layer (Layer 2) using MAC addresses.
7. What is the function of a firewall?
A. Increase CPU speed
B. Filter network traffic
C. Store backups
D. Assign IP addresses
Answer: B
Rationale:
Firewalls control incoming and outgoing network traffic based on security rules.
8. Which storage type offers the fastest performance?
A. HDD
B. SSD
C. Optical drive
D. Tape drive
Answer: B
, Rationale:
SSD (Solid State Drive) uses flash memory, making it much faster than
mechanical drives.
9. What does POST stand for?
A. Power On Self Test
B. Program Output System Test
C. Primary Operating System Tool
D. Pre-Operational System Transfer
Answer: A
Rationale:
POST checks hardware functionality when a computer starts.
10. Which connector is commonly used for modern monitors?
A. VGA
B. HDMI
C. PS/2
D. Serial
Answer: B
Rationale:
HDMI supports high-definition audio and video signals.
11. What is the purpose of DNS?
A. Encrypt data
B. Convert domain names to IP addresses
